Some vehicles today are equipped with predictive safety systems or adaptive cruise control systems. Such systems may monitor the vehicle surroundings and determine a position for another vehicle near a vehicle equipped with such a system. Such a system may calculate whether there will be a collision between the vehicle and the other vehicle, and in such case warn a driver of the vehicle.
Some safety systems may calculate a time until a possible collision between a host vehicle and another vehicle. If a collision is expected, emergency braking may be activated for preventing the collision.
In US2010085238A1, is described a driver assistance system with two object position-finding systems. One first object position-finding system is formed by a radar sensor, and is determined by analysis of radar signals. A second object position-finding system includes a monocular position data for one or more located object video system, with a front mounted video camera facing forward and an image processing module. A first module is arranged to calculate a first time to collision based on data from the radar sensor, and a second module is arranged to calculate a second time to collision based on input from the video camera. The two different times to collisions are then compared. If correspondence between the first time to collision and the second time to collision is found, an increased certainty that the located object is a real object is gained.
EP1500562B2 relates to a collision protection apparatus of a vehicle, comprising a camera unit, a bumper sensor and a radar unit. A relative speed to an object is calculated based on an output from the radar unit. During a collision, which is detected by the bumper sensor, input from the camera unit is used to calculate coordinates of the object.
In some situations it may be advantageous to use information collected by both a radar system and a front facing camera, for example, information collected by one system can be verified or compared to information collected by a different system. However, such a system requires many different components which have to cooperate in an intended manner, and such a system may therefore be both expensive, complex and heavy. Thus, improvements in the field of vehicle safety parameter control, by the use of a determined closing velocity, are still desirable.